Basis of Presentation and Summary of Significant Accounting Policies - General Liquidity Concerns (Details) - Senior Notes - USD ($) $ in Billions	Aug. 04, 2020	Dec. 12, 2019
Exit Notes, 11.00 Percent Due 2024
Stated interest rate on debt		11.00%
Face amount of debt		$ 2.1
Senior Notes 8.75 Percent Due 2024
Face amount of debt	$ 0.5

Face (par) amount of debt instrument at time of issuance.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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